PR 3225 Universal Frequency Converter

The PR 3225 Universal Frequency Converter is ideal for protecting rotating machinery by monitoring critical speed, over speed, and under speed. Additionally, it's useful for synchronous motors that turn or vibrate. For this purpose, the 3225, from PR electronics, can also match new speed sensors to original units and control process temperature, pressure, or flow without the use of a separate controller.

• measures frequencies up to 100 kHz
• active current output
• buffer voltage output 10 VDC
• 2-point process calibration
• user-programmable trigger levels -0.05 to 6.5 V and sensor supply 5 to 17 V
• NAMUR sensor error detection
• output relay with windows, set point, and latch functionality
• simulation of process value during commissioning / maintenance
• fast response time, with simultaneous sensor error detection (PATENTED)
• all terminals have over-voltage protection, polarity protection, and short-circuit protection
• ATEX certification for installation in hazardous areas

PR 3225 Universal Frequency Converter from PR electronics

For easy deployment, the typical configuration can be achieved via DIP-switch programming. With the optional PR 4590 ConfigMate and communication interfaces in the PR 4500 Series, it is easy to monitor and program the measurement point and take advantage of the advance features of the PR 3225. Due to the strong foundation of the PR electronics 3000 series with powerful features such as high accuracy, fast response time, and low temperature drift, the PR 3225 is a flexible and easy-to-use product when measuring frequency signals. With outstanding EMC specifications that meet or exceed industry standards and its 5-year warranty, users can look forward to many years of trouble-free operation with PR 3225.

• accuracy < 0.06% / span
• response time < 30 ms
• 2.5 kVAC, 3-port galvanic isolation
• wide ambient temperature range -13 to 158˚F (-25 to 70°C)
• NAMUR NE21, NE43

What are Frequency to Current Converters

The process industry requires measurement and control of many process variables. Speed and flow rate are two such variables, where safety and product delivery demand accurate process control. Sensors used to measure speed often take the form of proximity sensors, which detect a target as it passes by the sensor, thus resulting in a pulse or frequency output proportional to the speed. To enable these signals to interface with downstream equipment, the pulses or frequencies are often converted to a current or voltage signal. Frequency to current converters such as the PR 4225 and PR 3225 are ideal for this purpose.

Easy Programming and Installation

• easy configuration via DIP-switches
• factory calibration in all selectable measurement ranges
• configuration, monitoring, and diagnostics using PR 4500 detachable communication interfaces via the PR 4590 ConfigMate
• all programming can have password protection
• scrolling help text in 7 languages
• units can mount side by side, horizontally, and vertically, without air gap on a standard DIN rail, even at 158˚F (70˚C) ambient temperature
• units can receive power separately or together through a PR 9400 power rail
• the narrow 6.1 mm housing allows up to 163 units per meter

Speed Monitoring with a Frequency Converter

• independent speed measuring with alarm to monitor critical equipment
• verification of critical functions to ensure accurate measurement
• frequency converters are a great alternative to other tachometers, for example, a variable frequency device (VFD), rotation speed monitor,  or frequency transmitter such as S1SD-1FI-1R, MCR-2-F-UI-2902056, Jumpflex 857-500, KFD2-UFC-1.D, and more